1. Field of the Invention
The present invention relates to a self-alignment retaining device for a bass drum with which the peripheral edge of the bass drum is able to be securely clamped without any damage or tilting of the bass drum.
2. Description of Related Art
With reference to FIG. 8, a conventional retaining device (60) for a bass drum has an upright stand (not numbered), a base (61) and a clamping arm (63). The upright stand securely extends upward from the base (61). The base (61) has a slanted upper face (62) extending out from the upright stand. The clamping arm (63) is pivotal with respect to the base (61) and aligns with the slanted upper face (62) of the base (61). An adjusting screw (64) extends through the clamping arm (63) to engage the slanted upper face (62). When the retaining device is used to secure the peripheral edge of a bass drum (70), the adjusting screw (64) is screwed into the slanted upper face (62) of the base (61). The adjusting screw (64) forces the clamping arm (63) to pivot downward toward the slanted upper face (62) of the base (61). As the clamping arm (63) approaches the slanted upper face (62), the peripheral edge of the bass drum (70) is securely clamped between the clamping arm (63) and the slanted upper face (62).
However, because the upper face (62) of the base (61) is inclined and the bottom face of the clamping arm (63) is flat, the clamping arm (63) does not engage the slanted upper face well. The clamping arm (63) only exerts even pressure on the upper face (62) when the clamping arm (63) and the upper face (62) are in actual contact. Consequently, the bass drum (70) might tilt due to the uneven pressure between the slanted upper face (62) of the base (61) and the clamping arm (63) as the clamping arm (63) is pivoting downward relative to the base (61).
Furthermore, when this type of retaining device with the clamping arm (63) fixed with respect to the base (61) is used, the entire retaining device together with the striking mechanism (not shown) must be moved to clamp the edge of the bass drum in a different position, which is troublesome and time consuming.
With reference to FIG. 9, another conventional retaining device (170) is shown, wherein the clamping arm (72) is pivotal relative to the stand (71) and is connected by shafts (73) to an adjusting screw (74). With this arrangement, the foregoing problems still occur when trying to clamp the peripheral edge of the base drum.
To overcome the shortcomings, the present invention tends to provide an improved self-alignment retaining device to mitigate and obviate the aforementioned problems.
The primary objective of the present invention is to provide a self-alignment retaining device for a bass drum. The self-alignment retaining device includes a position plate, a first clamping plate and a second clamping plate. The position plate is securely mounted on the base and has an arcuate top face. The first clamping plate is pivotally connected to the position plate and has a bottom, a top and an arcuate recess in the bottom to receive the arcuate top face of the position plate. The second clamping plate is movable relative to and selectively engaged with the first clamping plate. The engagement between the arcuate top face of the position plate and the arcuate recess of the first clamping plate ensures secure and smooth positioning of the clamping surfaces of the first and second clamping plates on the periphery of the bass drum.
Another objective of the invention is to provide a torque device to drive the second clamping plate to move toward the first clamping plate so as to secure the periphery of the bass drum with the first clamping plate.
Still another objective of the invention is to provide an adjusting device to the self-alignment retaining device so that only part of the self-alignment retaining device is moved.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.